Indus river dolphins are one of only four river dolphin species and subspecies in the world that spend all of their lives in freshwater. They are believed to have originated in the ancient Tethys Sea. When the sea dried up approximately 50 million years ago, the dolphins were forced to adapt to its only remaining habitat—rivers. Only 1,816 exist today in the lower parts of the Indus River in Pakistan. Numbers declined dramatically after the construction of an irrigation system. Most dolphins are confined to a 750 mile stretch of the river and divided into isolated populations by six barrages. They have adapted to life in the muddy river and are functionally blind. They rely on echolocation to navigate, communicate and hunt prey including prawns, catfish and carp.
The main reason for the initial decline of the Indus river dolphin population was the construction of numerous dams and barrages that began in the 1930s. This construction split the population into small groups, degraded their habitat and impeded migration. Now the major threats include accidental capture in fishing nets, plus they are hunted for their meat, oil and for use in traditional medicines.
Untreated sewage from communities that reside along irrigation canals and the banks of the Indus River directly pollutes the water. Washing clothes and utensils in the river also causes pollution. Industrial pollution has allegedly caused a massive quantity of fish deaths in urban areas, which affects the Indus river dolphins’ food supply. Pesticides from sugarcane and cotton crops also pollute the riverbank.
On a brighter note, Indus river dolphin numbers have increased dramatically over the past 16 years, thanks largely to successful community-based conservation efforts. A new WWF survey says there are now an estimated 1,816 of them in Pakistan. This is 50% more than the 1,200 dolphins estimated after an initial census in 2001 when the species appeared to be on the brink of extinction.
Please like us and share.
Commentaires